A motorist travelling in the wrong inside lane on the Sydney Harbour Bridge is believed to have caused this morning's horror three vehicle crash.
Police, ambulance crews and the RTA have been praised for the quick response to the smash, which caused major traffic delays in this morning's peak.
Assistant Police Commissioner Catherine Burn, said a north-bound car has merged into the path of an oncoming garbage truck and another car heading south.
"A vehicle was traveling north-bound across the Harbour Bridge and as they got to the middle of the Harbour Bridge they've merged into another lane, lane five, and they've collided with the garbage truck which was coming in the opposite direction."
NSW Premier Morris Iemma has said he understands commuter frustration after this morning's peak-hour horror, but has defended authorities for their handling of the situation.
Trains were also interrupted because a rescue helicopter had to land on the bridge and transport a critically-ill patient to hospital.
Mr Iemma says authorities did all they could to move the wreckage quickly.
“Look, I can understand people’s frustrations,” he said.
“But let’s also remember that there is a man who is critically ill in hospital as a result of a very serious accident.
“The helicopter had been required to respond, the emergency services did respond and respond quickly. The transport management centre swung into action and did so quickly.”
But NSW Nationals leader Andrew Stoner says it's not good enough.
"What we need is an integrated plan which involves notification to commuters early, an early clearance of the wreckage and a greater use of public transport on those days."